Method and device for adapting link of v2x communication system

Abstract

According to the exemplary embodiment of the present disclosure, the method and the device for adapting a link of a V2X communication system acquires an appropriate parameter value to efficiently perform the link adaptation in the V2X communication system, thereby improving an average data transfer rate, determines an MCS level based on the state value (effective SNR) acquired in consideration of the device movement speed to build a V2X communication system which adaptively operates according to the state of the device.

What is claimed is: 
     
         1 . A link adapting method of a V2X communication system performed by a link adapting device which performs link adaptation based on information received from another link adapting device which is a communication target, the method comprising:
 receiving device state information from another link adapting device; and   performing link adaptation with the other link adapting device based on the device state information,   wherein the link adaptation is performed by:
 acquiring device movement speed information based on the device state information, acquiring a weight value using the device movement speed information based on a predetermined maximum speed, acquiring an offset value using the weight value, acquiring a state value using the offset value, and performing the link adaptation based on the state value. 
   
     
     
         2 . The link adapting method according to  claim 1 , wherein the link adapting method is performed by a processor mounted in a first vehicle, the other link adapting device is a second vehicle or a roadside base station terminal which is located in the vicinity of the first vehicle, the device state information includes relative movement information according to relation motion between the first vehicle and the second vehicle or the load side base station terminal, and the link adaptation is performed to determine a step size to adjust a level of a modulation and coding scheme (MCS) for link adaptation using the relative movement information. 
     
     
         3 . The link adapting method according to  claim 1 , wherein in the performing of link adaptation, the link adaptation is performed by adjusting a modulation and coding scheme (MCS) level based on the state value. 
     
     
         4 . The link adapting method according to  claim 3 , wherein in the performing of link adaptation, the link adaptation is performed by acquiring the MCS level which satisfies a predetermined target block error rate (BLER) from the state value. 
     
     
         5 . The link adapting method according to  claim 1 , wherein the device state information comprises a first state information for checking state change of a wireless channel and a second state information for checking a movement speed of a device, and in the performing of link adaptation, the state value is acquired based on the first state information and the second state information. 
     
     
         6 . The link adapting method according to  claim 5 , wherein in the performing of link adaptation, the state value is acquired by adding the offset value to an estimation value acquired based on the first state information. 
     
     
         7 . The link adapting method according to  claim 6 , wherein in the performing of link adaptation, the weight value is acquired based on the second state information. 
     
     
         8 . A link adapting device which performs link adaptation based on information received from another link adapting device which is a communication target, the link adapting device comprising:
 a RF transceiver which transmits/receives a RF signal;   a memory which stores one or more programs to perform the link adaptation; and   one or more processors which perform an operation for the link adaptation according to one or more programs stored in the memory,   wherein the processor receives device state information from another link adapting device by means of the RF transceiver and performs link adaptation with the other link adapting device based on the device state information,   wherein the link adaptation is performed by:
 acquiring device movement speed information based on the device state information, acquiring a weight value using the device movement speed information based on a predetermined maximum speed, acquiring an offset value using the weight value, acquiring a state value using the offset value, and performing the link adaptation based on the state value.